Optimization of radiation dose for CT detection of lytic and sclerotic bone lesions: a phantom study.

Details

Serval ID
serval:BIB_1CDAB7B06553
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Optimization of radiation dose for CT detection of lytic and sclerotic bone lesions: a phantom study.
Journal
European radiology
Author(s)
Greffier J., Frandon J., Pereira F., Hamard A., Beregi J.P., Larbi A., Omoumi P.
ISSN
1432-1084 (Electronic)
ISSN-L
0938-7994
Publication state
Published
Issued date
02/2020
Peer-reviewed
Oui
Volume
30
Number
2
Pages
1075-1078
Language
english
Notes
Publication types: Journal Article
Publication Status: ppublish
Abstract
To determine the best compromise between low radiation dose and suitable image quality for the detection of lytic and sclerotic bone lesions of the lumbar spine and pelvis.
A phantom was scanned using the routine protocol (STD, 13 mGy) and six decreasing dose levels. Raw data were reconstructed using level 3 of iterative reconstruction (IR3) with 1-mm slice thickness for the STD protocol and highest IR levels with 3-mm slice thickness for the others. CTDI <sub>vol</sub> was used for radiation dose assessment. Quantitative criteria (noise power spectrum [NPS], task-based transfer function [TTF], and the detectability index [d']), as well as qualitative analysis, were used to compare protocols. NPS and TTF were computed using specific software (imQuest). d' was computed for two imaging tasks: lytic and sclerotic bone lesions. A subjective analysis was performed to validate the image quality obtained on the anthropomorphic phantom with the different dose values.
Similar d' values were found for CTDI <sub>vol</sub> from 3 to 4 mGy with IR4 and from 1 to 2 mGy for IR5 compared with d' values using the STD protocol. Image quality was validated subjectively for IR4 but rejected for IR5 (image smoothing). Finally, for the same d', the dose was reduced by 74% compared with the STD protocol, with the CTDI <sub>vol</sub> being 3.4 mGy for the lumbar spine and for the pelvis.
A dose level as low as 3.4 mGy, in association with high levels of IR, provides suitable image quality for the detection of lytic and sclerotic bone lesions of the lumbar spine and pelvis.
• A CTDI <sub>vol</sub> of 3.4 mGy, in association with high iterative reconstruction level, provides suitable image quality for the detection of lytic and sclerotic bone lesions, both at objective and subjective analysis. • Compared with the standard protocol, radiation dose can be reduced up to 74% for the lumbar spine and pelvis. • A task-based image quality assessment using the detectability index represents an objective method for the assessment of image quality and bridges the gap between complex physical metrics and subjective image analysis.
Keywords
Algorithms, Bone Neoplasms/diagnostic imaging, Humans, Lumbar Vertebrae/diagnostic imaging, Pelvis/diagnostic imaging, Phantoms, Imaging, Radiation Dosage, Radiographic Image Interpretation, Computer-Assisted/methods, Reproducibility of Results, Tomography, X-Ray Computed/methods, Image enhancement, Image reconstruction, Multidetector computed tomography, Spine
Pubmed
Web of science
Create date
13/09/2019 10:22
Last modification date
15/07/2020 5:26
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